The present invention relates to a device for securing an end portion of a cord wound up onto a storage reel, of the type comprising at least one engagement seat formed close to a circumferential edge of a disc-shaped flange of a storage reel, said engagement seat being arranged to slidably engage an end portion of a cord wound up onto a core carrying the disc-shaped flange at the end thereof for fixing the circumferential positioning of the end portion itself relative to the reel; at least one clip secured to an outer surface of the side flange and arranged to engage an end portion of said cord in order to fasten it to the outer surface of the flange.
The invention is in particular but not restrictively relevant to storage reels of the type used for storage and transportation of cords, generally made of a wire or similar threadlike manufactured articles of an overall diameter in the range of 0.5 to 1.5 mm, which cords are usually used in making reinforcing structures of elastomeric material articles, such as motor-vehicle tires, conveyor belts, pipes and the like.
It is known that cords used in the reinforcing structures of elastomeric material articles are produced by suitable cord-making machines which also carry out winding of the cord as it is produced onto an appropriate storage reel. This reel lends itself to be then used for the cord storage and during the transportation steps from the production station to the places where the cord is to be actually used and the reel will then become a proper supply reel for the machine designed to make reinforcing structures provided with said cord.
The reel essentially comprises a substantially cylindrical core onto which the cord being produced is wound forming coils disposed consecutively in side-by-side relation and overlapped in successive radial outward layers. In order to carry out an appropriate holding of the coil pack, associated with the opposite ends of the core are two disc-shaped flanges concentric with the core, the outer diameter of which substantially defines the maximum diameter that the coil pack formed with the cord wrapped onto the reel can accommodate.
Also associated with at least one of the disc-shaped flanges of the reel is a device adapted to conveniently retain the end portion of the curd in order to avoid undoing of the coil, following loosening of the cord-winding tension.
In this connection, reels presently in use essentially provide that close to the outer circumferential edge of at least one of the flanges a through hole ("engagement sent") be formed for the purpose of slidably engaging the end portion of the cord in order to fix the circumferential positioning thereof relative to the reel by means of said device. The cord end portion coming out of the through hole towards the outside of the disc-shaped flange is engaged to a clip essentially consisting of a thin plate element made of harmonic steel (that is manganese-silicon, spring steel) material fastened to the disc-shaped flange through clipping of the circumferential edge of said flange to one end of the thin plate element. The cord end piece is therefore engaged by forced fitting between the outer surface of the disc-shaped flange and the clip, so that it is fixedly retained by effect of friction generated by the spring reaction of the clip itself.
In order to facilitate interchangeability of the clip which is subjected to frequent breakages because it is submitted to important flexion stresses at the fitting of the clipped circumferential edge of the flange, devices have been conceived in which the clip is fastened by means of its terminal appendages snap-fitted into an undercut formed by the circumferential edge of the disc-shaped flange turned outwardly.